We determined the effects of self-pollination and resource addition on reproduction in wild lupine (Lupinus perennis), a potentially threatened species in Ohio, and an indicator of the threatened Oak Savannah plant community. We used a factorial design with two pollination levels (control vs. selfing) by two nutrient levels (control vs. fertilizer/water addition). In this randomized blocks study (N = 64 plants), we randomly assigned each plant within a block to one of the four treatments. Our results confirm that wild lupine is self-compatible and revealed that reproduction varied significantly among maternal plants and among treatments. Self-pollination significantly reduced fruit number and mature seeds per inflorescence. Resource addition significantly increased fruit number and mature seeds, as well, and also increased early aborted seeds per plant. ANOVA indicates that selfed and naturally pollinated plants responded similarly to resource addition. However, of the 16 selfed plants receiving extra resources, 100% set some seed, while only 62% of the control plants would self-pollinate, indicating that the propensity to self may nonetheless be resource-dependent.

Shi X., H. J. Michaels, and R. J. Mitchell. The effects of self-pollination and resource addition in wild lupine, Lupinus perennis. (in prep.)